Enhanced BiVO4 photocatalytic and photoelectrocatalytic oxidative desulfurization performance via electrodeposited copper oxide nanoparticles

Zohreh Tahmasebi, Mohamad Mohsen Momeni, Alireza Najafi Chermahini, Applied Physics A

129, 2023, 

CuO@BiVO₄ photocatalysts have been synthesized through electrochemical deposition on an FTO glass as the photoanode in this work. Different techniques have been used to characterize the crystal structure, morphology, elemental composition and photoelectrochemical properties of synthesized photoanodes. The photocurrent responses of CuO@BiVO₄ were higher compared with those of bare BiVO₄, which indicates the band alignment between the two semiconductors giving rise to the prevention of fast recombination of electron–hole pairs. CuO@BiVO₄ samples show a photocurrent of 68 µA/cm² at 1.0 V Ag/AgCl electrode, which is eightfold the corresponding value for bare BiVO₄. Photooxidation of dibenzothiophene (DBT) was carried out to evaluate the photocatalytic oxidation activity of the samples prepared. The highest desulfurization rate of DBT was shown by sample CuO@BiVO₄ (15 cycles), according to the experimental results. In addition, the effects of reaction time, DBT and H₂O₂ concentrations, temperature, and various electrical biases on the rate of desulfurization were investigated by photocatalytic oxidation desulfurization reactions. Using a 0.9 V bias potential gave a degradation efficiency of 80% in the photoelectrocatalytic oxidation of DBT. The synergistic effect of photocatalytic and electrochemical degradation was responsible for the highest degradation efficiency in photoelectrocatalytic oxidation. Furthermore, based on the results of the experiments on the trapping of active radical species and the recyclability of the catalyst, •OH and •O₂⁻ radicals were found to be the active species and considerable stability was shown by the catalyst. The system shows outstanding stability and reusability and could be recycled seven times with no important reduction of photocatalytic activity, which suggests its adequacy as a photoanode for photocatalytic and photoelectrocatalytic oxidation of various pollutants in aqueous environment and wastewater

https://link.springer.com/article/10.1007/s00339-023-06487-3